Textured floor covering and process of making same



Dec. 9, 1930. I c. ELLIS 1,784,802

TEXTURED FLOOR COVERING AND PROCESS OF MAKING SAME Filed Dec. 2, 1926 FIBER, ETC. TEXTURED SURFRCE.

BASE

Patented Dec. 9, 1930 UNITED STATES CABLE-TON ELLIS, OF MON 'I'CLAIR, NEW JERSEY, ASSIGNOR TO ELIlIS-FOS'I'EB COMPANY,

PATENT OFFICE- A CORPORATION OF NEW'JERBEY 'mnx'runnn rrooa covnanza AND rnocnss or ammo-same This invention relates to floor coverings containing a cellulose ether or ester as the primary or essential plastic and bindipg agent, and relates particularly to floor cover ings containing nitrocellulose.

like, may be utilized. 7 r

For illustrative purposes, and not by way of limitation, there is shown in the drawing a cross section-of a floor covering made in accordance with the'present invention.

The paper material does not need to be prepared from high grade expensivefibre,

but may be made from ground wood," with perhaps some addition of sulphite fibre, and

"the like, to add strength. Various cheap fibres may be employed since the paper backing is practically concealed, being in contact with the floor. The paper may be dyed in different colors, if'desired, so as to correspond in tone with that of the tread composition, or may be of any other shade. Preferably such paper is rendered water resistant. This does not mean that it is necessarily absolutely waterproof, but a suflicient amount of a waterproofing agent, preferably is present, to preclude disintegration in case the floor becomes wet or when the floor covering is used in a damp locality that absorption of moisture will not causeany undue swelling of the paper backing with consequent distortion or buckling. v

In some cases asphalt-saturated paper of a grade known as felt may be employed.

This saturated felt is highly water resistant,

but has the disadvantage when white or delicately tinted floor coverings are desired, of

soiling the tread composition or throwing it off shade. This is due to small particles of the black material working into the tread composition from the rolls usually employed for sheeting. Even a small amount of black particles or exudation's from the saturated felt may alter the color undesirably. Therefore, as stated, for light colored floor cover- Application filed December 2, 1926. Serial H0. 152,809. I

ings, I preferably donot employ a paper backing saturated with black materials.

A suitable paper for backing purposes made from ground wood and ,sulphite pulp carries some rosin size to give strength and wax particles preferably introduced mto the paper by adding dispersions or emulsions of araflin wax or other waxes to the pulp in the I eater engine. In this way a wax-sized paper is obtained, which although containing but a small amount of wax, say from 1 to 5 per cent, is quite water resistant. Paper appropriate for the foregoing purpose is described in U. S. Patents Nos. 1,607 ,517-8-9, and 1,607,552 all of November 16, 1926.

Thin paper preferably is used for the backing, and in order to avoid splitting of'laminations, enough rosin size or other binder should be present to cause the fibres to adhere tightly. Papers of the kraft type are useful when waterproofed in the manner aforesaid. I prefer to use a thin paper for several reasons. In the first place the paper itself does not afford any great amount of cushioning effect and I preferably rely on the tread composition applied to the paper to obtain such a cushioning quality. In the second place a v heavy paper, unless saturated with some ma-' terial like asphaltor pitch, is prone to expand when in a moist place and cause bucklin A paper which is only thick or stiff enoug to be passed through the sheeting" rolls and receive a layer of tread composition is satisfactory and does not introduce any objectionable amount of paper stock into the product. While I have thus stated. the preferred form of the invention, I do not wish to be limited to the employment of such thin paper, but may use thick papers as occasion requires and may employ saturated felt as 'conditions warrant. j

Preferably the paper has" a rough texture or open surface, for example, showing marks of screens or felts employed" in making the paper, preferably being uncalendered or only lightly calendered and preferably free from oily substances orsuch a quantity of waxes as would serve to repel the nitrocellulose tread composition and prevent proper backing does not at any time peel away from the tread. Nitrocellulose does not adhere well to surfaces oiled with, for example, mineral. oil. It does not adhere well to a Waxed surface, but by employing a wax emulsion in making the paper, and having the latter possess a fairly rough surface, adequate adherence of the tread compositionresults. The repellant effect of nitrocellulose on wax is recognized, and I believe the employment by me of waxed paper to which a nitrocellulose composition will actually adhere constitutes a novel feature in the floor covering industry.

A suitable paper may be made from ground wood and sulphite pulp as aforesaid, having a thickness of about mm. and containing 2 or 3 per cent of rosin size, and from 1 to 5 per cent of wax size.

The paper may carry various fireproofing salts or substances having a fireproofing and waterproofing effect, as for example, hydrated calcium sulphate, some of the highly chlorinated compounds of benzol or napthalene, chlorinated petroleum asphalt, andthe like. Any substances to go into the paper for fireproofing or for other reasons should not have a harmful effect on nitrocellulose. For example, the latter is affected by alkaline substances and therefore it is not desirable to have any condition of alkalinity'which will have an objectionable effect on the nitrocellulose contacting with the paper surface.

As a floor covering should rest flat on the floor and as thick paper is liable to curl, the employment not only of thin paper, but of paper impregnated with substances which render it more flexible or pliable, or which absorb moisture and keep the paper from becoming bone dry sometimes are desirable. Salts such as calcium chloride or magnesium chloride are hygroscopic and also have some fireproofing qualities. Glycerine and glycol likewise may be employed for such special result. The paper may be impregnated with resins which do not have any objectionable discoloring effect on the tread material and which afford more waterproof products. In some cases certain vegetable oils, and the like, may be introduced into the paper structure.

The tread composition may be applied to the paper backing in various ways, but I prefer applying it with the aid of sheeting rolls These are of the type used in milling rubber and for calendering purposes. Pref erably differential rolls are employed, that is, one roll runs slightly faster than the other.

These sheeting rolls may beset to feed the; paper horizontally through" them or their position may be altered so the paper feeds vertically down through the rolls or other.

angles of feed may be employed.

The composition employedjfor sheeting preferably is of a putty -like consistency, or

even slightly stiffer than putty. When a mass of it is squeezed in the hand preferably liquid should not exude nor should it stick very readily to the hands. Preferably it should be as dry as is consistent with applying it to the sheet of paper in a smooth layer. Such a putty-like product when made according to the preferred form of the invention has nitrocellulose as the primary cementing or binding agent, incorporated with plasticizer and filling material preferably of a fibrous character.

Antacid materials may also be present and in many cases I prefer to employ a certain proportion of volatile solvent, as will be more fully hereinafter set forth.

The sheet of paper is fed through the rolls and while it progresses the plastic tread material is placed on the paper before the rolls and as paper and plastic pass therethrough, the tread composition is squeezed ti htly into contact with the paper and thus orms the tread surface.

Such tread surface may be further rolled or calendered while still plastic to smooth the surface, or to disturb it in order to give texture, all depending on the character of the surface finish desired.

In some cases it is possible to extrude a sheet of the tread composition and permit it to fall on a traveling sheet of paper, the latter serving as a backing either temporary or permanent. In other cases, especially when a high proportion of binder is present, it is possible to eliminate the paper backing entirely.

Floor coverings of the linoleum type as made today, have a smooth surface. This gives a severe kitchen-like effect and limits the applications of linoleum to a very considerable degree. On the other hand, roughfinished textured effects would afford a type of floor covering of much greater artistic possibilities than the harsh smooth and even glossy surfaces of the present day linoleum, Congoleum, and so forth.

A suitably textured floor covering may be made from nitrocellulose, as will be hereinafter more fully described.

Light colored effects have an important field of application. A pure white floor covering is desired because of its sanitary appearance. Rubber, boiled oils, and resins such as are employed in present day floor coverings make it difficult to obtain a pure white. Using nitrocellulose, it is possible to obtain a practically pure white tread. Having such a pure color, it is then possible to add various tints and obtain new effects, for example, soft green, rose, pastel shades, and the like, which-are not obtainable if the ground color is not pure white. This, if coupled with the aforesaid textured effect. enables floor rugs to be made, which because of their artistic appearance, may be used in variegated manner.

the home or in hospitals, public buildings,

and the like in a widespread manner.

The procedure therefore overcomes the kitchen-like severity of ordinary linoleum and ields new decorative -efiects of great possibilities.

Having obtained'a white or light-colored background it'becomes possible to introduce into the sheeting small masses of other and more intense colors and thus obtain mottled or variegated color effects. This result ma be obtained by adding small articles of co ored tread composition to t e mass of the main "tread composition as it is passing through the sheeting rolls. A better procedure is to sheet'the main tread composition on the paper backing and as it emerges from the sheeting rolls to scatter small masses of colored tread composition over the moist surface and allow the sheet to pass through a second se'tof rolls, thereby rolling the colored masses into the tread and squeezing such masses over the surface to distribute them in a Thus, innumerable multi-colored or polychrome eflects may be obtained. x

If desired, instead of using two sets of rolls there may be a plurality of rolls and 'difl'erent colored masses added between the different rolls, all while the li ht-coloredv ground mass of the tread is suciently moist and plastic.

Using a white ground, for example, and adding small particles of green plastic composition, will give a product with a white background and splotches or streaks of green. In a similar manner white and rose, or white and black combinations may be sccured. t

The addition of such supplemental colors is not as well carried out on a single set of rolls, that is, conducting the operation of sheeting and coloring all on one set of rolls as by the use of auxiliary rolls. There is a greater tendency when using a single set of rolls in getting some of the coloring compositions so much mixed in with the main tread composition that the latter becomes simpl discolored and the well defined mottled e fects desired are not produced in the same satisfactory-manner. Purity of the ground tone color is highly important and the present invention makes it possible to secure technical results of the character specified through the availability of such pure ground colored tread composition. p

In somecases-also it is proposed to ext rude onto a light-colored tread composition tiny streams ofcomposition of a stronger color and cause the sheeting to pass through a second set of rolls, whereby the extruded material is impressed intot-he main tread composition.- This enables stripes of color to be obtained. If the extruding. tubes are given a' lateral movement while the sheeted material is fed forward, the stripes will have an undulating character. i

Again, it is possible to reverse the color effect and to apply lighter coloredfmaterial in small proportion to a dark pigment.

In making the plastic composition I may employ nitrocellulose of high viscosity or of low viscosity, or may use mixtures of these.

Also, it is possible to use scrap celluloid and. other nitrocellulose waste or products which may not be suited for other purposes, as for example, to make smokeless powder. Since a floor coverin contains nitrocellulose dis- ,or what is termed Fcelluloid cotton as the binding agent. This has great toughness and a viscosity which is desirable in some sheeting operations. The viscosity reckoned in terms of lacquer viscosity is approximately 25 or 30 seconds, or may be higher, for example, 35 seconds. Nitrocellulose having a viscosity of 4 or 5 seconds also may be us (1. I

With the celluloid cotton or nitrocellulose I preferably employ a plasticizer such as dibutyl or diamyl hthalate, acetin, triphenyl and tricresyl p osphates. The tricresyl cizer because of its tendency torender nitrocellulose slow burning. By incorporating a sufficient amount ofthe tricresyl phosphate along with a substantial proportion of mineral filler and possibly using some chlorinated hydrocarbon to saturate the paper' backing a relatively and notably fire resistant floor covering may be obtained.

Castor oil or 'rapeseed -oil, preferably of the blown'type, sometimes may be added to the composition to yield greater flexibility.

A floor covering or rug which flattens effectively isobtaineddesirably by incorporation with the celluloid cotton or other nitrocellulose of a quantity of an appropriate resin, one which is compatible with nitrocellulose. A series of resins have been dephosphate is especially desirable as a plastiscribed by me in copending applications, as for example, in Serial Nos. 149,528, 150,387,

142,532 and 144,647. Appropriate resins are' those ma by reacting glycerine or glycol with various crystallineorganic acids-or an-' Ill - compatible synthetic resin, the desired flattening eflect ma be secured.

As pigment tliere may be used, for white sheeting such substances as lithopone, zinc oxide, white lead, sublimed lead, lead sulphat, barytes, chalk,-and the like. Titanox is also a strong white, but is not wholly a pure white, and in some cases has been observed to have an action on nitrocellulose. Some of the i ments have an antacid eflect which is desira le. Colors or pigments are added to tint as desired.

Certain mineral substances such as calcium sulphate containing the maximum amount of water of hydration are desirable as fillers because they tend to reduce the inflammability in a very marked way. v

In addition to the mineral antacids I may use organic antacids such as urea or amines.

The character of the fibrous material employed as filler, is important as on this to a certain extent depends the strength and flexibility of the tread and its cushioning effect. Asbestos fibre, ground wood, sulphite pulp, and the like, may be used, according to the character of the floor covering desired. When a cream colored finish or darker effect is wanted, ground cork of a fineness passing sa -80 meshis useful.

or a white textured effect a considerable proportion of cotton flock, linters, bleached sulphite pulp, and the like, may beused;

The greater the proportion of material I such as cotton flock, employed, the more tex- A solvent frequently is required inrendering the nitrocellulose composition sufliciently plastic to be smoothly or adequately sheeted and such solvents may be those which are known ashigh boiling in the lacquer ingiving off a large amount 0 'tified even after the dustry, as for example, primary and secondary butyl and amyl alcohol and their acetates, diacetone alcohol, ethyl lactate, butyl propionate, and so forth. Using these high-boiling solvents allows plenty of time to work out thecomposition on the rolls and themasses of material on hand do not dry out so quickly that their use in a commercial way becomes unfeasible.

However, such high boilin solvents are more expensive than some of the more volatilesolvents. Acetone, for example, is much cheaper and is a Very powerful solvent for nitrocellulose. Furthermore, acetone solutions have a viscosity lower than those made with some of the high boiling solvents. This is sometimes advantageous in securing a good sheeting effect, Methyl acetone also may be used, likewise, methyl and ethyl acetate. Isopropyl acetate is'not as powerful a solvent, but may be used to advantage as it is fairly cheap. Associated with the nitrocellulose solvents may be various diluents for the sake of cheapness, as for example, benzol and toluol, light petroleum benzine, monochlorobenzol, and the like.

However, the employment of such cheap highly volatile solvents brings with it the difficulty that the masses of material on hand in the workroom dry out too guickly, besides vapors which pollute the air. To obtain a workable composition which remains plastic for an indefinite period, I introduce a small amount of a mineral wax, as for example, ceresin or paraflin wax. This gives to the composition two very useful qualities. In the first place, it does not dry out quickly at room temperature, but remains plastic and workable for a relatively long time. In the second place, itdries out very quickly at temperatures above, say, 100 F. 1 Thus, it becomes possible to dry and sheet the composition very rap- V idly. This is not true with some of the high boiling solvents mentioned, these .requiring more protracted heating, and even so, the odor sometimes is retained in a thick tread composition for a longl time and may be idennished rugs have been kept for some time. 1 I

For this reason the addition of wax is ady vantageous, since a plasticity is maintained on exposure at room temperature over a considerable period and moreover, drying when desired, takes place quickly, requiring a relatively compact drying chamber. The odor is eliminated from the goods speedily and" is not retained so as to be offensive when the rug is subsequently unrolled on thefioor,

Various waxes having a polishing characteristic, such as carnauba, Montan, beeswax, or shellac wax, may be added, in some cases. Hot calendering enables a more polished surface to be obtained when desired.

Sometimes it is desirable to have the sol-.

also because it may be used for dilution of a nitrocellulose solvent vantage.

In order to secure a non-inflammable plastic a solvent for nitrocellulose should be used mixture to greater adwhich is not too highly inflammable. Acetone and methyl acetate are less suited than ethyl acetate, isopropyl acetate, andsome of the higher esters Mixtures of isopropyl acetate or isobutyl acetate with trichlorethylene, when incorporated with nitrocellulose, filler, plasticizer and tricresyl phosphate, with or without a synthetic resin or preservative solid, will be found to possess verylittle, if any, tendency to inflame on bringing, for example, a lighted match, near a mass of the material. If a flame is held in contact with the material for a suflicient length of time the solids themselves may take fire, but the rate of combustion is comparatively slow and the fire hazard therefore is greatly reduced. Incorporation of wax in such a composition greatly reduces the tendency to evolution of vapors and this is desirable notonly from the standpoint of fire hazard, butbecause the mass of material for sheetingis maintained in a state of uniformplasticity over a considerable period.

In some cases chlorinated ethylene, that is, ethylenedichloride, or Dutch liquid, may be used to reduce inflammability.

- Whilethe desirability of using a volatile solvent, that is, quick-dr ing, after the completion of sheeting has heen emphasized, it should be understood'that I do not exclude sheeting with hot rolls without solvents, but with suflicient plasticizer and/or resin to obtain an inadequate softening effect. Such hot sheeting cannot be carried out very satisfactorily with ordinary asphalt-saturated felt becausethe temperature of sheeting is usually higher than the melting point of the saturating material and the latter is therefore squeezed out of the felt between the rolls.

There are cases also ,when wateremulsions of nitrocellulose and plasticizer may be employed, using for example, bentonite as an emulsifying agent.

When it is not appropriate to produce a tread of sufiicient thickness in one sheeting operation, a tread may be formed, dried and asecond layer of tread composition sheeted-on the first, so that there is 'obtained one tread layer superposed on another.

rality of tread layers.-

On the other hand, it is also feasible to sheet first on one side of the paper support and then to sheet the other side. In this way be obtained a floor covering suc This procedure maybe repeated,-if desired, to obtain a plutreads opposed to oneanother are obtained and rugs or runners may be made in this mannerwhich are reversible. When one side has been worn out the rug is reversed and a fresh tread surface becomes available. These opposed tread layers may, if desired, be of different colors.

One form of the invention is that in which the rugs, runners or other forms of floor covering take for shi ment. 7 To prepare for transportation the oor covering is rolled so that the flexible sheeting support of paper backing is on the inside, while the tread com-' position faces outwardly, that is, a cross section of the roll would show the tread of each s iral or convolution facing outwardly, while t e paper support would be facing inwardly. This, of course, applies to products having the tread on only one side of the paper backing. By rolling in this manner the tread surface is maintained in a state of extension, a condition which is highly desirable, especially in the case of surfaces of the textured character described. Rolling such .rugs with the tread roll form comprising a flexible sheeted support carrying a nitrocellulose tread composition, as for example, one having a textured surface; said roll having the tread composition facing outwardly, whereby the tread face is maintained in a state of extension.

In accordance with the foregoing there may as a rug,

runner, or strips, (latter being int ded to be laid in parallel, e. g, to cover a floor completely); said floor covering being preferably substantially self-flattening and non- .curling, that is, when laid does not persist in curling upwards at the ends or corners, although not fastened to the floor. The invention also contemplates a floor coverin which is slow-burnin ,-.that is, one which oe's not exhibit any undue fire hazard, also, one which .is sufficiently. water-resistant to stand exposure to such contact, with water as is. likely under reasonable service conditions; moreover, a floor covering which preferably has a substantial cushioning effect, that is, has ade-'- quate softness underfoot due to a resilient tread of appropriate thickness; said floor covering being composed of, or comprising a flexible sheeting support, e. g., paper, waterproofed paper, waxed paper, wax-sized paper, and the like, carr'yinga nitrocellulose tread composition adapted for underfoot usage; such floor covering preferably hav ing an ornamental surface secured by the use of pleasing colors, variegated colors, textured finish, and the like. v

Ate'xtured effect such as is obtained by embossing a'design by means of rolls is not as satisfactory as the method of destroying waste.

the smooth continuity of the surface to ob-- tain an irregular reflection of light by sheeting material containing fibrous masses which are somewhat lumpy 'and which on passing through the sheeting rolls form the rough surface noted. The employment of embossing rolls, however, is not precluded in some cases.

In one form of the invention, a volatile solvent, or water, is present in the plastic tread composition and after sheeting this on a support, the product is rapidly heated to cause bubbles or pores to form. When this has progressed sulficiently the sheet may be re-rolled to smooth out the surface somewhat. A more cushiony effect is obtained in this way. The combined effect of this with a resilient filler such as wood flour or ground cork is advantageous from the cushioning standpoint.

Another filling material which may be used to good advantage in making a more fire resistant product is vegetable ivory This material in the form of fine fragments or dust is a by-product of the manufacture of buttons, and the like. It does not have the same combustibility as, for example, wood fiour. Being very light in color it can be used freely in making lightcolored and variegated products.

When paper is used as the backing material, in addition to impregnating it with ammonium phosphate and incorporating, for example, parafiin wax as a waterproofing agent, I may also use chlorinated naphthalene such as the tetra or penta chloride of naphthalene, perchlorinated benzol, chlorinated asphalt, and the like, as sizing or waterproofing agents. These chlorinated compounds confer fireproof qualities as well as acting as waterproofing agents. In addition, chlorinated naphthalene, and the like, may be incorporated in the tread composition as a polishing agent and also to depress combustibility.

A feature of my invention is the employment of mineral salts containing water of crystallization or hydration. A salt which is suitable for the purpose is finely-ground or precipitated calcium sulphate containing 2 molecules-water. If plaster of Paris, that 1s, calcined calcium sulphate, is moistened with water, it gives up more than 2 molecules water and this perhydrated sulphate is a useful filler to employ in making tread compositions; In order to obtain fire resistance to a high degree I preferably employ a substantial proportion of the perhydrated calcium sulphate.

In some cases nitrocellulose, as for ex;- ample, celluloidstock, may be used wet with water;- This avoids drying the nitrocellulose prior to use and enables it to be stored safely and to be handled with a considerable degree of impunity. In using such material, if

in such a manner that the nitrocellulose mass becomes heated to an objectionable degree due to the reaction of hydration.

When wet nitrocellulose is employed and .all the water is not absorbed by a dehydrating filler,the nitrocellulose may be converted into a kind of an emulsion with plasticizer and possibly a solvent such as butyl acetate or amyl acetate not miscible with water. Additional Water may be added if desired in order that a putty-like material results when the bulky filler is added. In other words, the water serves to replace a volatile solvent in whole or in part, to produce the putty-like sheeting composition.

When triphenyl or tricresyl phosphate is used as a plasticizer for nitrocellulose in tread compositions which are white or lightcolored, the employment of zinc oxide or certain other basic bodies as antacids may result in a slightsaponification of the plasticizer with the liberation of phenols and the possible discoloration or pigmentation due to such phenolic substances. This alteration, unless of considerable extent, may be of very slight consequence with some of the variegated tread surfaces,'but the-case may prove quite different with an extremely light-colored or pure white tread. Plasticizers which do not have any discoloring action on pigments and antacids which do not have a saponifying action on triphenyl phosphate or tricresyl phosphate may be used. In one form of the invention I contemplate using, for example, tricresyl phosphate as the principal plasticizer with pigments, fillers or antacids inert or innocuous'thereto. Likewise, when synthetic resins such as those of the glyceride type mentioned above are employed, preferably a basic pigment is avoided which will saponify the resin and cause hardening or brittleness. Hence I prefer to employ pigments, fillers and antacids substantion on these resins.

From the foregoing it will appear that I with nitrocellulose, so I prefer to employ pigments, fillers and antacids which are compatible with nitrocellulose, synthetic resins and plasticizers.

As anillustration celluloid nitrocellulose containing alcohol, used to moisten it during i parts of hydrated calcium sulphate, 175 parts of white pigment including lithopone and 50 parts of finely divided vegetable ivory was used. 5 parts of paraffin wax also were incorporated to render the composition slow drying at room temperature.

The materials were thoroughly incorporated, making a white putty, which was sheeted on various forms of backing, including paper. After sheeting the moist sheeting product was dried gradually up to about 7 5 C. The solvent was rapidly removed at this temperature.

The textured effect of a very marked type was obtained by forming fragments of tread composition still plastic but dried out somewhat and applying such fragments helter skelter to a freshly sheeted surface, then passing through rolls. The somewhat harder lumps of the dried tread composition imparted a notable texture to the surface in this manner.

Another tread composition was made from 500 parts'by weight of nitrocellulose, dry

weight, (moistened with denatured alcohol) 665 parts plasticizer, 400 parts acetone, and 300 parts benzol. The nitrocellulose was allowed to soak over night in the solvents and plasticizers and thoroughly mixed the fol lowing morning in a Werner-,Pfleiderer mixer. Therewas added 750 parts cork dust, 80 mesh, 750 parts lithopone, parts chrome green. The composition also included 12 parts ceresin wax. Finally 200 parts each of acetone and benzol were added to obtain a more plastic putty.

Large sheets of blotting paper, manila pa per and saturated felt base were sheeted'with this composition and dried-at about 45 C. When drying had progressed sufficiently a second sheetlng of material was applied to the first. Good surfaces were obtained.

Some of the samples were placed in a hydraulic press in contact with a polished sheet of metal and were pressed for five minutes at 500 to 1000 lbs. pressure, the press being heated by steam at 20 lbs. pressure. This phate. Or, if more fireproofresults are desired, the plasticizer may be entirely tricresyl phosphate. v

Variegated results are obtained, for example, by sheeting the light-colored composition set forth above and applying to the surface green composition set forth in the second formula given in the third preceding paragraph above. In this manner a two-color or mottled and streaked effect is secured.

f Still another composition was prepared rom:

Partsby weight Celluloid nitrocellulose 400 Denatured alcohol 160 Tricresylphosphate 612 Acetone 320 Bsnzol 240 Paraflin wax 20 Urea 4 Cottonseed fattyacid phthalic glyceride resin dissolved in an equal weight of volatile solvent 400 (200 parts actual resin) After thorough incorporation the follow- This produced a white mix. A good yellow tone was obtained by adding 20 parts chrome yellow.

The volatile solvent used to dissolve the synthetic resin was a mixture of equal parts toluol and secondary butyl acetate.

The composition sheeted satisfactorily on saturated felt and on paper which was not impregnated. I

Products were obtained ranging from a heavy tread to one which was merely a veneer. The best results with such veneers were obtained with saturated felt as a cushioning support.

A glossy smooth finish was obtained by pressing the dry sheeted product between polished metal plates in a hydraulic press at 1000 lbs. pressure per square inch and at a temperature corresponding to 20 lbs. steam pressure.

In one case blotting paper was saturated with a solution made from 1 part by weight diammonium hydrogen phosphate in 2 parts water. The paper then was dried and some of the last mentioned tread composition was sheeted thereon to form a floor covering product. This material could not be ignited by the flame of a match.

Finally I wish to emphasize the feature that in the preferred form of the invention the plastic material when prepared for sheeting-is not self-supporting in thin layers of the thickness of the intended tread. This elimination of volatile solvents.

however, causes a cementatlon of the sheeted at irregular distances small portions of the is likewise true after sheeting and before Drying,

mass. aud strengtheningof the tread. The paper or other'support'so needful therefore to carry thetread layr in its freshlysheeted condition becomes less important after drying. The ratio of thickness of the tread support to the tread itself varies according to requirements. On the one hand thin kraft paper may carry a thick tread (double-sheeted) or thick saturated felt may have merely a veneer of the cellulose ester plastic. The ratio thus may be greatly varied.

The employment of highly volatile solvents permits the sheeting'operation to take place without artificial heat,"hence may be carried out at room temperature. Blistering, due to the evolution of water vapors from the fille rs and the like in hot rolling s Well as other objectionable features of hot rolls, is avoided.

Using felt saturated with soft pitch or asphalt to give pliability makes hot rolling in sheeting on a veneer of nitrocellulose tread composition a matter of great practical difficulty. On the other hand. the employment of highly volatile solvents anchored at room temperature in a tread composition by wax and readily released at slightly higher temperatures enables such veneer to be applied quickly and cheaply.

Also, I wish to note that using such solvents and wax a remarkably adherent tread results even to a paper backing containing a very considerable proportion of wax waterproofing.

There is ,shown in the drawing a base A which may be of paper or other flexible material as described above, carrying a tread composition B, which may be any of the compositions set forth above, and particularly containing nitrocellulose with the other compositions. The tread layer B carries a textured surface C, which in the preferred form of the invention illustrated in this case involves fibrous material which has been so manipulated as to produce a texture marked surface, such as the flow marked surface, particularly described herein.

What I claim is 1. As a floor covering, a flexible sheeting support carrying a sheeted nitrocellulose tread composition of non-uniformly 'textured surface.

2. A'floor rug consisting of a wax-sized 1 paper backing carrying a nitrocellulose tread composition of flow-marked surface.

3. The process of making a floor covering which comprises sheeting on a paper backing a plastic tread composition comprising nitrocellulose and fibrous material, the latter being present in substantialquantity, and manipulating. during the sheeting operation 4. As a floor covering, a flexible support of paper made from paper stock carrying wax deposited therein from a Wax emulsion,"

carrying a tread composition containing nitrocellulose and asynthetic resin, the surface of said tread being textured.

5. As a floor covering, a flexible thin paper support of roughened surface and an adherent nitrocellulose tread composition containing a soft synthetic resin and a plasticizer, the tread surface being textured.

6. As a fioor covering, a flexible sheeting support carrying a nitrocellulose tread composition containing a synthetic resin, said tread being irregularly textured on its surface, the floor covering being noncurling.

7. A floor rug having a nitrocellulose tread composition carrying irregularly distributed fibers whereby a textured surface is obtained.

8. The process of making a floor covering which comprises sheeting on a paper backing a tread composition comprising nitrocellulose and white fibrous material to form a non-curling, self-flattening rug.

9. A floor rug having a light-colored nitrocellulose tread composition carrying irregularly distributed light-colored fibers whereby a textured surface is obtained.

10. A floor rug having a white nitrocellulose tread carryin considerable quantities of irregularly distributed light-colored fibers and suflicient nitrocellulose and pigment to fill in around the fibers, whereby a dense but textured surface is obtained.

11. A floor rug as set forth in claim 9, in which the tread composition includes a synthetic resin compatible with the nitrocellu lose.

' CARLETON ELLIS. 

